Make Fetch and FetchAuth available as services

[wanze]

First of all, thank you for creating this Addon, it rocks! 👍

We had the need to customize the authentication by only allowing registered users to consume the Fetch API.

• This pull request registers the Fetch and FetchAuth classes as singleton services in Laravel's service container, allowing them to be extended or decorated.
• Furthermore we needed to add some CORS headers to the response returned by Fetch. I tried to add them via custom HTTP middleware, but it seems that these are getting bypassed when the request is handled by an Addon controller in the frontend. The Addon now emits an event when the response is created, allowing event listeners to modify the response (similar to Statamic's response.created) event.

Note that the constructor of the Fetch class changed its signature, as we need a dependency injection for the FetchAuth class. Parameters are now injected via Fetch::setParameters(). I am not sure if you consider this a BC break. Other than that, the changes should be fully backwards compatible.

Here is an example for a custom decorated FetchAuth service:

// The decorated service
class FetchAuthDecorator extends FetchAuth
{
    private $fetchAuth;

    public function __construct(FetchAuth $fetchAuth)
    {
        $this->fetchAuth = $fetchAuth;
    }

    public function isAuth()
    {
        if (!$this->fetchAuth->isAuth()) {
            return false;
        }

        return User::loggedIn();
    }
}

// The registration in the service provider
$this->app->extend(FetchAuth::class, function ($fetchAuth) {
    return new FetchAuthDecorator($fetchAuth);
});

Cheers

[aryehraber]

Hi @wanze, this looks and sounds great! I'll try and properly review and test in the next week or so when I find some time. Thanks for the contribution!

[aryehraber]

Hey @wanze, sorry about the delay on this! Finally had a chance to have a closer look at the changes and test it locally.

I found 1 small bug but can fix that easily on my end before creating the next release. In case you're interested in what was wrong, you correctly added the new setParameters call on the Tag but not the Controller, so none of the params worked there anymore.

Thanks again for the PR, I think this was a really clean way to go about it and I learned some new things from your changes 😄